Method and apparatus for inspecting vacuum packed receptacles



June 28, 1966 H. F. [RMEN 3,25812@ METHOD AND APPARATUS FOR INSPECTING VACUUM PACKED RECEPTACLES Filed Oct. 10, 1963 9 Sheets-Sheet 1 "my. 147 162 1 I 5 NIH: WW. 163a llln 155 1565 1 715 Huh -I Um 171.. ump II /\I 155a. l I 15 W 1 a 107 l" I l v5 Admin. W0

INVENTOR. Hon/212D I [EMEN June 28, 1966 H. F. IRMEN 3 METHOD AND APPARATUS FOR INSPECTING VACUUM PACKED RECEPTACLES Filed Oct. 10, 1963 9 SheetsSheet 2 q a G 5 INVENTOR. HOE/242D I [FMEN June 28, 1966 H. F. IRMEN 3,258,120

METHOD AND APPARATUS FOR INSPECTING VACUUM PACKED RECEPTACLES Filed Oct. 10, 1963 9 Sheets-Sheet 5 INVENTOR Home!) I [EMEN A nezmw June 28, 1966 H. F. IRMEN 3,258,120

METHOD AND APPARATUS FOR INSPECTING VACUUM PACKED RECEPTACLES Filed Oct. 10, 1963 9 Sheets-Sheet 4 15 0714 120 I [EMEN W/mw June 28, 1966 H. F. IRMEN 3,258,120

METHOD AND APPARATUS FOR INSPECTING VACUUM PACKED RECEPTACLES Filed Oct. 10, 1963 9 Sheets-Sheet 5 INVENTOR. ZYOWHPD F. JRMEN June 28, 1966 H. F. IRMEN 3,258,120

METHOD AND APPARATUS FOR INSPECTING VACUUM PACKED RECEPTACLES Filed Oct. 10, 1963 9 Sheets-Sheet 6 125 l t l i a l W jjlllimpdz ri INVENTOR. HOWARD I fZMEzV MW ///M June 28, 1966 H. F. lRMEN METHOD AND APPARATUS FOR INSPECTING VACUUM PACKED RECEPTACLES 9 Sheets-Sheet 7 Filed Oct. 10, 1963 "'"nhl w'" g INVENTOR. Hmmz F ZZ June 28, 1966 H. F. lRMEN 3,258,120

METHOD AND APPARATUS FOR INSPECTING VACUUM PACKED RECEPTAGLES Filed Oct. 10, 1963 9 Sheets-Sheet 8 I 0 $5 Ill 1 I'll: a .96 95 Q i/ )j a 101 6 86 /99 3 ih... 92 109 ilm I? 6.4 .94 INVENTOR.

Hon 220E [EMEN ATTOE/VEKS June 28, 1966 H. F. IRMEN 3,258,120

METHOD AND APPARATUS FOR INSPECTING VACUUM PACKED RECEPTACLES Filed Oct. 10, 1963 9 Sheets-Sheet 9 INVENTOR. HUWAPDF [KMEN JTTOEA/E/f United States Patent METHOD AND APPARATUS FOR INSPECTING VACUUM PACKED RECEPTACLES Howard F. Irmen, Minneapolis, Minn, assignor, by mesne assignments, to Geo. A. Hormel & Company, Austin, Minm, a corporation of Delaware Filed Oct. 10, 1%3, Ser. No. 315,247

40 Claims. (Cl. 20988) This invention relates to high-capacity method and apparatus for performing multi-mechanical inspection operations on filled receptacles formed of rigid material and containing a vacuum packed product, preferably food stuffs, to determine damage to the receptacle and to also determine if the contents of the receptacle packed therein are packed with sufiicient vacuum.

An object of this invention is to provide a novel highcapacity method and apparatus for performing in one cycle of operation, a plurality of inspection steps to determine damage to a receptacle formed of rigid material and containing a vacuum packed product, preferably food stuffs, and to also determine if the contents of the receptacle were packed therein under suflicient vacuum, and to automatically reject unacceptable receptacles.

A more specific object of this invention is to provide a novel method and apparatus for inspecting vacuum packed receptacles and which is especially adapted for continuous line operations in meat packing plants and the like, :and wherein the receptacles are successively fed into inspection cells of a multi-celled unit, and mechanically inspected to determine if the contents of the receptacles are packed under sufficient vacuum, each receptacle also having the bead thereof inspected for damage, and wherein acceptable receptacles are directed to a discharge station for further processing, and the imperfect receptacles are retained and rejected at a rejection station.

A further object of this invention is to provide a novel receptacle inspection method and apparatus of the class described with provision of mechanical sensing means interposed along the feed-in conveyor means to remove damaged receptacles from the in-feed line if the damaged receptacles are so deformed that they cannot be received within the inspection cells.

These and other objects and advantages of this invention will more fully appear from the following description made in connection with the accompanying drawings, where-in like character references refer to the same or similar parts throughout the several views, and in which:

FIG. 1 is a diagrammatic top plan view of the apparatus;

FIG. 2 is a vertical cross sectional view of the apparatus taken approximately through the vertical center line thereof;

FIG. 3 is a vertical sectional view on an enlarged scale of a single inspection cell of the apparatus and with certain parts thereof omitted for clarity;

FIG. 4 is a top plan view on an enlarged scale of a single inspection cell with certain parts thereof broken away for clarity and other concealed parts thereof illustrated by dotted line configuration;

FIG. 5 is an elevational View of a single cell on an I 3,258,120 Patented June 28, 1966 line 6-6 ofFIG. 4 and looking in the direction of the arrows;

FIG. 7 is a side elevational view of the in-feed mechanism;

FIG. 8 is a horizontal cross sectional view taken approximately along line 8-8 of FIG. 7 and looking in the direction of the arrows;

FIG. 9 is a vertical cross sectional view taken approximately along line 9-9 of FIG. 7 and looking in the direction of the arrows;

FIG. 10 is a front perspective view on an enlarged scale of certain of the elements of an inspection cell;

FIG. 11 is a horizontal cross sectional view on an enlarged scale taken approximately along line 1111 of FIG. 2 and looking in the direction of the arrows;

FIG. 12 is a detailed view of a mask plunger and drive therefor associated with each inspection cell; and

FIGS. 13 through 17 are diagrammatic front elevational views of the vacuum inspection mechanism illustrated in various positions with respect to a receptacle during the inspection cycle.

Referring now to the drawings and more specifically to FIGS. 1 and 2, it will be seen that one embodiment of the apparatus used in carrying out the novel method, is thereshown. It is pointed out that the novel method and apparatus described herein has been found especially adaptable for use in inspecting generally rectangular metal receptacles containing food stuffs, such as meat and the like, although the apparatus may be used to inspect other types of receptacles or containers. The apparatus disclosed herein and designated generally by the reference numeral 10, will be treated under separate headings for clarity.

SUPPORTING STRUCTURE The apparatus 10 includes a supporting structure, designated generally by the reference numeral 11, which includes a horizontally oriented lower plate 12 spaced above the floor of a building by vertical support posts 13. An upper plate 14 is spaced above and substantially parallel to the lower plate 12 and is also supported from the vertical support posts 13.

The reduced lower end of a vertically disposed central bearing post 15 is positioned within an aperture in the lower plate 12 and it will be seen that the central hearing post 15 projects upwardly through an aperture in the upper plate 14. This central bearing post 15 is successively reduced upwardly as at 15a, 15b, 15c and 15d, as best seen in FIG. 2, so that annular shoulders are defined at the respective lower ends of each of the diametrically reduced portions. A top plate or cover 16 for the apparatus is positioned upon the shoulder defined between the bearing post portions and 15d and is also supported by certain of the vertical support posts 13.

MULTI-CELL INSPECTION UNIT A multi-cell inspection unit 17 is revolvably mounted on the central bearing post 15 for concentric movement relative thereto. This multi-cell inspection unit 17 includes a plurality of identical inspection cells 18 each opening generally radially outwardly as best seen in FIG. 1. In the embodiment shown, twelve such inspection cells are provided and each individual inspection cell 18 is revolvable from a feed-in station to a discharge station for acceptable receptacles, and thereafter to a discharge station for rejected receptacles and is finally 3 returned to the feed-in station. In the embodiment shown, this multi-cell inspection unit is revolvable at approximately 13 r.p.m. and is continuously revolved during operation of the apparatus.

The drive mechanism designated generally by the refer ence numeral 19 for the multi-cell inspection unit 17 includes a drive sprocket 20 which is connectible to a suitable source of rotary power (not shown) such as an electric motor or the like. An idler sprocket 21 is journaled on a shaft 22 for rotation relative thereto, the shaft 22 being mounted on the upper plate 14 as best seen in FIG. 2. A large driven sprocket 23 is threadedly connected to the lower end of the multi-cell inspection unit 17 for rotation therewith. An endless chain 24 is trained around the drive sprocket 20, the idler 21 and the driven sprocket 23 to thereby supply drive to the multi-cell inspection unit. The power unit or electric motor may be mounted against either the upper or lower surface of the upper plate 14 although no such power unit is illustrated in the drawings.

The multi-cell inspection unit 17 includes a body structure 25 which is comprised of a cylindrical hub portion 26, the lower end of which is threaded to receive the internal threaded driven sprocket 23. The body structure 25 of the multi-cell inspection unit 17 is also provided with a relatively large lower annular flange 27 and a smaller upper annular flange 28. It will be seen from FIG. 2 that the lower annular flange 27 and upper annular flange 28 are integrally formed with the hub portion 26 and each projects concentrically outwardly relative thereto. It will also be noted that the hub portion has an enlarged internal diameter at its lower terminal portion to define a downwardly facing internal annular shoulder 26a which is positioned in bearing relation upon the shoulder defined between the lower portion of the central bearing post 15 and the next adjacent reduced portion 15a thereof. It will also be seen that the individual inspection cells 18 are mounted upon and releasably secured to the lower annular flange 27 and are also releasably secured to the upper annular flange 18.

INSPECTION CELLS Referring now to FIGS. 2, 3, 4 and 5, it will be seen that each of the inspection cells 18' is comprised of a substantially flat top wall 29, a rear wall 30 and a bottom wall 31 and defining a chamber or cell space therewithin. It will be noted that the top and bottom walls are of trapezoidal configuration and that the bottom wall 31 has a leg 33 integrally formed therewith and projecting downwardly therefrom. The leg 33 is provided with vertically extending threaded taps therein to receive the threaded ends of bolt and nut assemblies 34 and is also provided with transversely extending apertures to receive the nut and bolt assemblies 35 therethrough. It will be seen that the nut and bolt assemblies 34 project through the flange 27 of the body structure 25 while the nut and bolt assemblies 35 secure each cell to the upper flange 28. It will also be seen that the leg 33 is supported upon the flange 27, as best seen in FIG. 2, and that each of the cell units 18 has the cell space or chamber 32 opening outwardly.

Each inspection cell includes means for measuring the vacuum of the receptacle to determine if the contents of the receptacles are packed under a suflicient vacuum and each cell also includes the mechanism for inspecting the seam or bead of the receptacle. To this end, it is pointed out that it is contemplated that the particular receptacle to be measured is of generally rectangular configuration as illustrated in FIGS. 1 and 13 through 17. The respective upper and lower peripheries of the can are also provided with the conventional rolled beads or seams. Damage to the beads of such cans in addition to impairing the appearance of the cans quite often results in minute leaks which would permit the escape of fluid such as air into the can or receptacle, the interior of which contains a negative pressure or partial vacuum.

4 BEAD INSPECTION MECHANISM The seam or bead inspection means for each cell simultaneously inspects the peripheral bead or seam at both the upper and lower sides of the can and therefore an upper and a lower bead inspection mechanism is provided for each inspection cell. Since the upper and lower inspection mechanisms for each cell are substantially identical, identical reference numerals will be used for each of the corresponding elements and members of the respective upper and lower bead inspection mechanisms. The respective upper and lower head or seam inspection mechanisms, designated generally by the reference numeral 36, each includes a generally U-shaped can or receptacle guide member 37 comprised of a transversely extending web portion 38 having legs 39 integrally formed therewith and projecting longitudinally of the associated inspection cell space 32. The can guide member 37 of each inspection mechanism for each inspection cell is connected to the inner surface of the associated upper or lower wall of the associated inspection cell by suitable bolt assemblies 40, as best seen in FIGS. 3, 4, 5 and 10. It will also be seen that the inner peripheral surface of the can guide member 37 is provided with a plurality of arcuate recesses 39a, the purpose of which will be more clearly set forth hereinbelow.

Each head or seam inspection mechanism includes a tumbler or pin carriage member 41 which is of generally rectangular configuration and which has a plurality of circular recesses 42 therein. It will be seen that the recesses 42 of the upper bead inspection mechanism 36 face downwardly while the recesses in the lower head or seam inspection mechanism for each cell face upwardly. These recesses in each of the tumbler carriage member 41 define a generally rectangular pattern corresponding generally to the outline or profile of the respective upper and lower beads of the can to be inspected. Each of the recesses 42 has a small helical spring 43 positioned therein and each recess also accommodates a pin or tumbler element 44 therein. It will be seen that each pin 44 has a reduced upper end portion 45 whereby an annular shoulder 46 is defined intermediate the ends of each pin. Thus it will be seen that the tumblers or pins 45 for the lower carriage member 41 are urged upwardly by the associated helical springs 43 while the pins of the corresponding upper carriage member will be urged downwardly.

Each bead or seam inspection mechanism 36 also includes a relatively flat, generally rectangular shaped guide plate 47 which is disposed in abutting relation with respect to the associated tumbler carriage member 41. Each guide plate 47 has a plurality of apertures 48 therein corresponding in number to the number of pins 44 and each aperture 48 being of a size corresponding to the enlarged portion of the pins 44, to permit the pins to project upwardly therethrough. A substantially flat mask plate member 49 is positioned upon the guide plate 47 of each bead inspection mechanism 36 and is shiftable relative thereto. This mask plate member includes an enlarged generally rectangular front portion 50, a generally rectangular shaped intermediate portion 51, which is of reduced width, and a tongue or rear terminal portion 52, as best seen in FIGS. 4 and 10.

The intermediate portion 51 of each mask plate member 49 has a centrally located opening 53 therethrough, the purpose of which will be described more fully hereinbelow. It will also be noted that the mask plate member 49 also has a plurality of apertures 54 therethrough corresponding in number and size to the apertures in the associated guide plate 47. It will be noted that each aperture has a reduced slot portion 55 communicating therewith, the slots associated with the apertures 54 adjacent the side edges of the mask intercommunicating with adjacent apertures.

The flat portion 55 associated with each of the apertures 54 in the mask plate member 49, are of a size to permit the pins 44 to project upwardly therethrough but are of a width to prevent passage of the annular shoulder 46 of each pin upwardly therethrough. Thus when the slot portions associated with each aperture 54 are disposed in registering relation with respect to the axis of each pin, the pins will be retained in their retracted position.

The rear wall 30 of each cell 18 has a pair of recesses 30a therein, each recess accommodating one of the tongues or rear terminal portions 52 of each mask plate member 49 therein. Each recess 30a also has one end of a helical spring 56 positioned therein, the spring being disposed in embracing relation around the tongue 52 of the associated mask plate member and having its forward end abutting against the intermediate portion of the associated mask plate member. Thus for-andaft sliding movement of each mask plate member with respect to the associated cell 18 will be effected by the spring 56.

Each mask plate member 49 also has guide elements 57 integrally formed with the respective side edges of the front portion 50 thereof and these guide elements 57 are received within guide slots or recesses 58 in a pair of guide blocks 59. It will be noted that the lower pair of guide blocks 59 are mounted upon spacer elements 61 and are secured to the lower wall 31 of the associated cell by bolt assemblies 61 The upper pair of guide blocks 59 are secured by upper bolt assemblies 60a to upper spacer elements 61a, the spacer elements 61a being secured to the upper wall 29 of the associated cell by bolt assemblies 611), as best seen in FIG. 5. Thus it will be seen that the mask plate member 49 for each of the upper and lower bead inspection mechanisms for each cell 18 are shiftable in a fore-and-aft direction relative to the cell and relative to the associated tumbler carriage member 41 and guide plate 47. It will also be seen that when the mask plate member 49 for each head inspection mechanism 36 is retracted from the normal extended position, the apertures 54 will be moved into registering relation with respect to the longitudinal axis of the pins 44 and thus permit passage of the enlarged portion of the pins through the apertures 54.

Referring again to FIGS. 3, 4 and 10, it will be seen that each mask plate member 49 has a transversely extending cam element 62 fixedly carried by the front edge of the front portion 50 thereof. This cam element 62 has an arcuate front cam surface 62a which is engageable by a cam roller 63 during operation of the apparatus which cam roller causes retractive movement of the associated mask member against the bias of the associated helical spring 56 to permit the bead of the can to be inspected. Therefore, as pointed out above, when the apertures 54 and the mask plate member 49 are disposed in registering relation with respect to the longitudinal axis of the pins 44, the pins 44 will be urged upwardly through these apertures 54 in the mask plate member by the helical spring. When the cam element 62 is disengaged by a cam roller 63 the mask plate member 50 associated therewith will be urged forwardly by the 'spring 56.

The respective front edges of the upper and lower walls 29 and 31 of each inspection cell 18 are provided with hearing blocks 64 which are respectively secured thereto by means of bolt assemblies 65. It will be noted that the lower bearing block 64 is somewhat larger than the upper bearing block of the associated inspection cell. The upper and lower bearing blocks 64 are each provided with a pair of transversely spaced apertures therein for accommodating the bead inspection mechanism support rods 66 therethrough. It will be seen from FIG. 3 that each pair of the support rods 66 also extend through the rear wall 30 of the associated inspection cell and each pair of support rods 66 is axially shiftable relative to each inspection cell. Each of the support rods 66 has a pair of convex support elements 67 affixed thereto, the lower surface of the associated carriage member being engageable with and supported by the convex support elements of the associated support rods. The lower surface of each of the carriage members 41 also has an arcuate recess 68 formed in the surface thereof disposed adjacent the associated support rod 66, four such recesses being provided for each carriage member 41. The support rods 66 are normally positioned with respect to the associated carriage member 41, as illustrated in FIG. 3, so that the carriage member is supported upon these convex support elements 67. However, upon axial shifting movement of the support rods 66 in a forward direction, as illustrated in FIG. 3, the convex support elements 67 will be moved into registering relation with respect to the arcuate recesses 68, thereby permitting shifting movement of the associated carriage member 41 so that the arcuate recesses are seated upon the convex support elements 67.

In order to assure proper movement of the carriage to cause seating of the arcuate recesses upon the convex support elements 67, reference is made to FIG. 6 wherein it will be seen that each carriage member is provide-d with a laterally projecting ear 69 adjacent each corner thereof. Each of these ears 69 for each carriage member is suitably apertured and a flanged sleeve 70 projects therethrough. A bolt 71 extends through the sleeve 70 and is threaded into a threaded tap formed in the associated spacer element associated therewith. In FIG. 6, the lower bead inspection mechanism is illustrated, and it will be seen that the bolt 71 is threaded into a tapped recesses in the lower spacer element 61. A coil spring 72 is positioned around the sleeve 70 and bears against the flanged end of the sleeve and against the associated ear 69. Thus it will be seen that the carriage member 41 of the upper bead inspection mechanism is spring loaded upwardly while the carriage member 41 associated with the lower bead inspection mechanism is spring loaded downwardly. Therefore when the support rods 66 for each bead inspection mechanism 36 is shifted axially forwardly, the carriage member will be urged in a direction to seat the arcuate recesses 68 thereof upon the convex support elements 67 of the associated support rod 66.

During the bead inspection operation, the can to be inspected will be positioned in an inspection cell 18 and between the respective upper and lower can guide members 37. The respective upper and lower beads of the can will be positioned upon the pattern or profile defined by the apertures and slots formed in the mask member 50 for each bead inspection mechanism and the mask will be retracted by coaction of the cam roller and cam element 63 and 62 whereby to permit the pins 44 to escape from their retracted position. In the event that either the upper or lower bead of the can or receptacle is deformed, it will be seen that the enlarged portion of the pin 44 located in the vicinity of such deformed portion of the head will be shifted upwardly to obstruct return of the mask member to the extended position. It will be seen, however, that the locked mask plate member will be allowed to return to its extended position when the support rods 66 therefor are axially shifted to permit the carriage member 41 to have the arcuate recesses 68 thereof seated upon the convex support element 37 of the associated support rod. When this action occurs, the pins 44 which may be obstructing movement of the mask plate member will be shifted out of obstructing relation with respect thereto and permit extension of the mask member to its return position. In the event that the beads of the can being inspected are not damaged, the bead itself will prevent escape of any of the pins into obstructing relation with respect to the associated mask plate member. Thus the mask plate member will be returned to its normal extended position by action of the coil spring 56.

Means are also provided for positively locking the can into the inspection cell during the inspection cycle. To this end, referring again to FIGS. 3, 4 and 10 it will be seen that the mask plate member 50 of each head inspection mechanism has a lock supporting member 73 secured thereto for movement therewith. It will be not-ed that the lock supporting member 73 for the upper bead inspection mechanism is positioned above the associated mask while the lock supporting member for the lower bead inspection mechanism is positioned below the associated mask plate member. It will also be seen that the lock supporting member 73 for each mask plate member has a portion thereof positioned in close proximity and generally in obstructing relation with respect to the central opening 53 in the associated mask plate member. The lower surface of the lower lock supporting member 73 and the upper surface of the upper lock supporting member 73 are each recessed as at 74 to define a hook element 75 adjacent the rearmost end thereof.

Each lock supporting member 73 has a generally U- shaped lock member 76 pivotally secured thereto by means of a pivot pin 77. It will be noted that each lock member includes a substantially fiat web portion 73 having legs 79 integrally formed therewith. The web portion 78 is of a width to permit the legs 79 to be positioned on opposite sides of the lock supporting members 73 and it will be noted that the rear edge of the legs 79 are inclined to define oblique camming surfaces 86. It will therefore be seen that when the mask plate member 50 is retracted rearwardly, the lock supporting member and the lock member associated therewith are also carried rearwardly thereby.

The carriage member 41 and guide plate 47 for each inspection mechanism are each also provided with a generally centrally located opening therein, as best seen in FIG. 3, and the lock supporting member and lock member for each mask plate member is positioned in the opening of the associated carriage member and guide plate. The rear edge defined by the centrally located opening of each guide plate 47 actually defines a camming edge or surface 47a which cooperates with the camming surface 80 on each of the legs 79 for the lock member 76. Therefore when the lock member 76 is shifted rearwardly with the associated mask plate member, the camming surface 80 of the lock member leg 79 will be urged into engaging relation with the camming edge 47 on the associated guide plate. Thus the lock member 76 will be pivoted by its pivotal axis 77.

It will be noted that the web portion 78 of the upper lock member 76 has its lower surface disposed in substantially co-planar relation with the lower surface of the associated mask plate member while the lower lock mem- .ber 76 has the upper surface of the web portion 78 thereof disposed in substantially co-planar relation with respect to the upper surface of the lower mask plate member 50. However, upon pivoting movement, by the camming action each lock member will be disposed out of co-planar relation and will actually engage the bead of the can to be inspected and will obstruct movement of the can forwardly and outwardly of the inspection cel-l. Although not shown in the drawings, each of the lock members are provided with spring means to normally urge the lock members into co-planar relation with the associated mask plate member. Thus it will be seen that the upper lock member 76 will be spring loaded upwardly while the lower lock member 76 will the spring loaded downwardly. Therefore upon return of the mask plate member of each bead inspection mechanism to its normal position, the associated lock member 76 will also be returned to its co-planar orientation relative to the associated mask plate member.

VACUUM INSPECTION MECHANISM pressure. When the can or receptacle is subjected to a negative pressure, the sides of the can, as best seen in FIGS. 13 through 15, will be collapsed slightly inwardly depending upon the degree of negative pressure. It is desirable to create a sufiicient partial vacuum within the packed receptacle or can to minimize any tendency of the contents of the can from spoiling. In the event that there is a leak in the receptacle, the sides of the can will not be retained in the slightly concave collapsed relation and such packed can would be unacceptable for consumer sale. Therefore a vacuum measuring mechanism is provided to determine if a minimum adequate vacuum or negative pressure actually exists within the sealed interior of the can. The cross sectional width of the sealed receptacle generally centrally of the inwardly collapsed side walls thereof are therefore inspected to determine if the sides are collapsed inwardly a predetermined amount to indicate the presence of an adequate partial vacuum. If an insufficient partial vacuum or negative pressure exists within the interior of the can, the sides of the can will not be collapsed inwardly the desired predetermined amount.

The vacuum inspecting mechanism for each inspection cell, designated generally by the reference numeral 81, includes a pair of vertically disposed feeler shafts 82, each having opposite ends thereof secured in recesses in the adjacent upper and lower legs of the can guide members 36. Each shaft 82 has a feeler element 83 journaled thereon for rotation relative thereto. Positioning collars 84 secured to the shaft 82 by set screws 85 properly position each feeler element upon the associated shaft 82. In this connection, it is pointed out that the feeler elements each have arcuate inner feeler surfaces 83a which are positioned to be moved towards the inwardly collapsed or concave sides of the receptacle or can to be inspected during the inspection operation. Each of the feeler elements also includes an exterior arcuate cam surface 8312, as best seen in FIGS. 13 through 17.

Each vacuum inspection mechanism also includes a pair of vertical cam shafts 86 each having its upper end journaled in a suitable recess in one of the legs 39 of the upper can guide element 36, the lower end of each shaft 86 projecting downwardly through the leg element 39 of the lower can guide member and below the lower support rods 66 of the lower bead inspection mechanism 36. It will be seen that each shaft 36 is positioned in relatively close proximity to one of the feeler shafts 82 and substantially parallel thereto. Each cam sharft 86 has a rotary cam 87 keyed thereto for rotation therewith, each rotary cam element 87 having an eccentric peripheral cam surface 87a engageable with the camming surface 83b of the associated feeler element 83. Thus it will be seen that when the shaft 86 is revolved, the associated cam 87 will be correspondingly revolved whereby the cam surface 87a thereof will contact the cam surface 83b of the feeler element 83 to shift the feeler element about its support. Each pair of cam elements 87 are synchronized to be revolved to cause similar synchronized movement of the feeler elements 83.

Reference again is made to FIGS. 13 through 17 wherein a diagrammatic top plan view of the can to be inspected is illustrated during the vacuum inspection cycle. In FIG. 13, the cams and feelers are in the initial stage of the inspection cycle, and the rotary cam elements 87 will be rotated in the direction of the arrows. It will be seen in FIG. 14 that if a sufficient negative pressure or partial vacuum exists within the interior of the can, the cam elements can make a complete rotation in the inner eeler surfaces 83a of the feeler elements and will not be moved into engaging relation with respect to the concave sides of the can. In FIGS. 16 and 17, it will be noted that the respective sides of the can are not collapse-d inwardly and the cam elements 87 will revolve until the feeler elements are locked against the sides of the can.

This condition indicates that an insufficient partial vacuum or negative pressure exists within the can and the can is therefore unacceptacle. Therefore the can will be retained within the inspection cell until the multicell inspection unit 17 is rotated to position the particular inspection cell at the rejection discharge station.

Means are provided for driving the rotary cam elements 87 during the inspection cycle and to this end it will be seen that the lower end of each rotary shaft 86 has a driven gear 88 afiixed thereto. The driven gear 88 meshes with a drive transmitting gear 89 keyed to a shaft 90, the latter also having a drive gear 91 keyed thereon. It will be seen that each drive gear or pinion 9-1 meshes with one of a pair of racks 93 carried exteriorly by a drive transmitting sleeve 92, as best seen in FIGS. 3 and 11. The drive transmitting sleeve 92, as best seen in FIG. 3 is concentrically mounted upon a drive shaft 94, one shaft being provided for each inspection cell 18. It will be noted that the drive shaft 94 for each inspection cell extends through the rear wall 30 of each cell and through the lower bearing block 64 as best seen in FIG. 3. It will also be seen that this drive shaft 94 is spaced below the lowermost of the support rods 66 and is axially reciprocable relative to the associated inspection cell.

The drive shaft 94 has a generally U-shaped lock mounting member 95 mounted thereon for movement therewith. A lock member 96 is positioned between and pivotally connected to the legs of the U-shaped mounting member 95 by means of a pivot pin 97, a spring element 90 being interposed between the lower surface of the lock member 96 and the drive transmitting sleeve 92 to normally urge the lock member to pivot in a counterclockwise direction as viewed in FIG. 3. The lock member 96 has a lock element'96a formed adjacent the free end thereof and is also provided with a locking pin 99 which extends transversely thereof. It will be seen that since the lock mounting member 95 is affixed to the drive shaft 94 for movement therewith, the lock member 96 will also be moved with the drive shaft 94 during reciprocating movement thereof.

The drive transmitting sleeve 92 has a lock engaging member 100 integrally formed therewith. One end of the lock engaging member 100 is shaped to define a locking element 101 which, as shown in FIG. 3, normally engages the locking pin 99 during the inspection cycle to cause the drive transmitting sleeve 92 to be moved with the drive shaft 94. The spring 98 tends to urge the lock member 96 upwardly so that the locking pin 99 is urged into engagement with the locking element 101. A coil spring element 102 is positioned around the drive shaft and is interposed between the lower bearing block 64 of each inspection cell and the face of the lock engaging member 100. It will therefore be seen that the coil spring 102 resists forward movement of the drive transmitting sleeve 92.

It will be seen that when the shaft 94 is axially reciprocated, the inner locking action of the lock member 96 and the lock engaging member 100 interlock, the drive transmitting sleeve with the drive shaft 94 so that the rectilinear drive is transmitted through the racks 93 and through the gear train to the cam shaft and thereafter to the rotary cam elements.

In order to positively lock the can within the inspection cell 18 when such can has an insufficient partial vacuum, the feeler elements 83 will engage the sides of such :a can and will prevent further rotation of the rotary cam elements 87. The resistance of the rotary cams towards revolving movement will be transmitted through the gears 38, 89 and 91 and the racks 93 to the drive transmitting sleeve 92. The drive gear or pinion 91 will tend to hold the rack and drive transmitting sleeve 92 against movement with the shaft 94 whereby this resistance will be transmitted to the locking pin 99. Since the spring element 98 is a relatively weak spring, the lock member 96 will become disengaged from the lock engaging member thereby permitting relative movement of the drive transmitting sleeve 92 with respect to the drive shaft 94. When this occurs, the lock element 96 will be urged upwardly and will engage the hook element 75 of the lock supporting member 73. Upon further movement of the shaft 94 in a retractive direction, the lock supporting member 73 and the associated mask element will also be retracted. When this occurs, the lock member 76 will be urged against the camming edge 47a of the guide plate 47, therefore shifting the lock member 76 into obstructing relation with respect to the bead of the can being inspected. Thus the can will be retained in the inspection cell until the drive shaft 74 is shifted axially forwardly whereby the lock member 96 will be moved out of interlocked relation with respect to the lock supporting member 73. Thus it will be seen that the lock member 76 not only serves to retain the can within the inspection cell when such a can has a damaged head, but also is a locking means for retaining the can in the inspection cell in the event that such a can has an insufficicnt vacuum to collapse the sides inwardly the required predetermined amount.

Referring now to FIGS. 2 and 11 it will be seen that the actuating means for reciprocating the drive shafts 94 for each inspection cell comprises an eccentric generally circular cam plate 103 having a closed cam track or groove 104 formed therein. This cam plate 103 is mounted upon the shoulder defined by the portions 151) and 15a of the central support post 15. The cam plate is keyed to the central support post and the drive shafts 94 for the inspection cells 18 are moved angularly relative thereto. It will be seen that each drive shaft 94 carries a vertically disposed shaft 105 at its innermost end which is disposed substantially normal to the longitudinal axis of the drive shaft. Actually the shafts 105 constitute cam roller shafts and each has a cam roller 106 affixed to the lower end thereof, the rollers being disposed in the cam track 104. Since the shaft 105 is journaled for rotation in the end of the associated drive shaft 94 the cam rollers will travel very nicely in the cam groove track 104. 'Because of the eccentric configuration of the cam track 104, the drive shafts 94 will be caused to reciprocate axially during one complete cycle or revolution of the multi-cell inspection unit.

The drive mechanism for reciprocating the support rods 66 for the inspection cell 18 comprises a pair of actuator cam plates 107 each being eccentrically mounted upon the portion 50b of the central support post 15 for rotation relative thereto. The uppermost of the actuator cam plates 107 cooperates with the uppermost pair of support rods 66 for the inspection cells 18 while the lowermost of the actuator cam plates 107 cooperates with and actuates the lowermost of the support rods 66 of the inspection cells. It will be noted that each actuator cam plate 107 is mounted upon an eccentric bearing 108 and that the cam plate presents a plurality of substantially flat outer faces 109, each face being positioned in close proximity to the rear wall 30 for one of the inspection cells 18. Each face 109 has a pair of sockets 110 therein for accommodating the innermost ends of the support rods 66 therein. The pair of sockets in each face of the upper actuator cam plate accommodates the inner ends of the upper pair of support rods 66, the inner end of each rod 66 being connected by an adjustable pin element 111 with its associated socket.

It will therefore be seen that during rotation of the inspection cells 18 and the upper and lower actuator cam plates 107, the eccentric movement of the cam plates about the associated eccentric bearings 108 produces rectilinear movement of the support rods 66. These support rods 66 will therefore be moved relative to a tumbler carriage member 41 associated therewith to thereby permit movement of the convex support elements 67 to be moved into and out of seated relation with respect to the arcuate recesses 68. The speed of movement of the support rods d6 for each cell relative to the drive shaft 94 associated with each inspection cell is such that the lock member 76 will be retained in obstructing relation with respect to a defective can or receptacle within the cell by the lock member 95 during a predetermined distance of movement of the inspection cell 18 which contains the defective receptacle. This action will be described more fully hereinbelow.

Means are also provided for successively supplying each inspection cell 18 with a can or receptacle to be inspected and this in-feed mechanism, designated generally by the reference numeral 112, includes a support structure comprised of a substantially fiat, generally rectangular, upper plate 113 and a fiat, generally rectangular, lower plate 114 disposed in substantially parallel relation with the upper plate. The upper and lower plates are rigidly connected together by suitable nut and bolt assemblies 115 which extend through suitable spacer sleeves 116, as best seen in FIG. 7. The rear end portion of the in-feed mechanism 112 communicates with the discharge end of the conventional roller type gravity conveyor system used in material handling systems wherein the article to be conveyed travels by gravity over the rollers of the conveyor.

The lower plate member has a substantially straight, longitudinally extending shallow guideway 117 formed therein through which passes the cans or receptacles C to be inspected. The in-feed mechanism 112 also includes means for removing any can or receptacle which is so deformed that the defective receptacle cannot be received within the inspection cells 18. This means includes a first endless skimmer belt member 118 trained about a pair of conical rollers 112, as best seen in FIGS. 7 and 9. The rollers 119 are each provided with a roller shaft 120, the roller shafts being journaled in suitable bearings 121 affixed to the lower surface of the upper plate 113.

It will be seen that one of the roller shafts 120 has a driven gear or pinion 122 affixed thereto for rotation therewith and that this pinion is disposed in meshing relation with respect to another pinion or gear 123 keyed to the shaft 124 of a conventional electric motor unit 125. Thus when the motor 125 is energized to drive the shaft 124, the drive pinion or gear 123 will drive the driven pinion or gear 122 to thereby drive the first skimmer belt 118 to the right as viewed in FIG. 9. The cans or receptacles which are so deformed that the receptacles will pass just below the in-feed side of the lower run of the first skimmer belt 118 will be laterally directed from the guideway 117 and will not pass through the iii-feed mechanism 112. It will be seen that the electric motor unit 125 which supplies power to the first skimmer belt 118 is mounted by suitable bolt means upon the upper plate 113.

The in-feed mechanism also include-s means for rejecting cans which are slightly deformed to a degree to prevent entry into the inspection cells 18 but which are not deformed to the degree to cause rejection thereof by the first skimmer belt 118. This means detects and removes cans which have been vertically compressed and which as a result of the compression are laterally distended. Referring again to FIGS. 7, 8 and 9 it will be seen that a vertically disposed plate 126 is affixed to the lower plate 114 and is positioned adjacent one longitudinal peripheral edge of the guideway 1 17 in the bottom plate. A spring urged plate 127 is positioned oppositely of and parallel to the fixed vertical plate 126 and along the other side of the guideway 117, the plate 127 being shiftably mounted by suitable bolt assemblies on a backing support plate 128 and normally urged in a direction towards the fixed vertical plate by resilient spring elements 129. Just forwardly and slightly laterally of the spring urged pressure plate 127, a track member 130 is afiixed to the upper surface of the lower plate 114. This track member 139 has an inclined ramp or trackway 131 thereon which is inclined upwardly in a forward direction.

A second endless skimmer belt 132 is trained around a pair of rollers 133 and extends transversely of the guideway 117 and above the fixed plate 126, the spring urged pressure plate 127 and the track element 130, as best seen in FIG. 7. It will be seen that each belt roller 133 is provided with a roller shaft 134 journaled in suitable bearings 1'35 afiixed to and depending from the lower surface of the upper plate 113. It will be seen that one of the roller shafts 134 has a driven pinion or gear 136 keyed thereto which is disposed in driven relation with respect to the drive pinion 123. Therefore when the motor 125 is energized, the skimmer belt 132 is also driven in the same direction as the skimmer belt 118.

When a can which is vertically compressed and laterally distended passes below and beyond the first skimmer belt 118, the can because of its distended width will not be positioned precisely within the relatively shallow guideway 117. The can will pass between the fixed plate 126 and the spring urged pressure plate 127. Since the can is of a width slightly greater than the spacing between the vertical plates 126 and 127 the can will abut against the fixed plate 126 and will urge the pressure plate 127 outwardly. When this condition occurs, the can will be guided positively upon the ramp 131 whereby the can will be tilted so that at least a portion of the upper surface of the can will be engaged by the second skimmer belt 132 and will be laterally ejected. The gear marginal edge portion of the pressure plate 127 is flared slightly outwardly to facilitate entry of a defective can between the plates .126 and 127. It is also pointed out that the rounded peripheral edges of the conventional meat containing receptacles also facilitates entry of the can between the plates 126 and 127.

Means are also provided for accelerating movement of the cans to be inspected after the cans have passed beyond the second skimmer belt 132. This means includes a pair of rows of vertically disposed, generally cylindrically shaped driven accelerator elements 137. These accelerator elements 137 in the embodiment shown, comprise vertically disposed pins preferably covered with a somewhat resilient compressible material such as rubber or the like and extending between the respective upper and lower plates 113 and 114. It will be seen that the rows of accelerator elements 137 are spaced-apart and define a passage therebetween. The upper terminal portion of each accelerator element 137 has a pulley 138 affixed thereto for rotation therewith. It will be seen that a plurality of idler pulley shafts 1 are afiixed to the upper plate 113 and project upwardly therefrom. These idler pulley shafts each have an idler pulley 139 journaled thereon for rotation relative thereto. It will be seen that the idler pulleys are arranged in a pair of rows,

;' the pulleys comprising one row being staggered with relation to a pair of the driven pulleys 138.

An elongate endless drive belt 141 is trained around the drive pulleys and idler pulleys in a sinuous fashion and provides drive for the accelerator elements 137. The endless drive belt 141 is also trained around a relatively large pulley member 142, the latter being journaled for rotation around a relatively short pulley shaft 143 which is affixed to the upper plate 113 and projects upwardly therefrom. The output shaft 124 for the electric motor unit also has a drive pulley 145 keyed thereto for rotation therewith and the drive belt 141 is also trained around this drive pulley. It will therefore be seen that when the motor unit 125 is energized, the drive belt and accelerator elements will also be driven whereby cans passing between the accelerator elements will be accelerated towards the multi-cell inspection unit 17. It is pointed out that the spacing between the accelerator elements 137 is such as to snugly and engagingly accommodate the receptacles or containers to be inspected.

Referring now to FIG. 1 it will be seen that the inspection apparatus includes a feed-in station 146, an acceptance discharge station 147 and a reject discharge station 148, the stations being circumferentially spaced from each other. The acceptance discharge station is the station wherein the cans which have been inspected and found to be acceptable are discharged for further processing while the reject discharge station 148 is that station wherein the unacceptable cans are discharged.

Referring again to FIGS. 2 and 3, it will be seen that means are provided for normally urging a can from each inspection cell 18 and this means includes a plunger mechanism 149. This plunger mechanism 149 includes an elongate cylindrical plunger bearing sleeve 150 for each cell, each bearing sleeve 150 being pressed in axially extending relation in a centrally located aperture in each cell rear wall 30. A plunger sleeve member 151 is slidably positioned within each bearing sleeve 150 and each sleeve member 151 has an elongate coil spring 152 positioned therein. It will be noted that the front end of each sleeve member 151 is opened and that a plunger cap 153 is slidably mounted thereon, the cap projecting outwardly into the associated cell chamber 32. An actuator cam 154 is affixed to portion b of the central hearing post 15 and the outer periphery of this cam is maintained in engaging relation with the rear end portion of the associated sleeve member 151. Although not shown in the drawings, in the embodiment illustrated, the sleeve member 151 will be provided with a cam roller for engagement with the outer peripheral edge of the cam 154 to thereby facilitate camming movement of the sleeve member 151.

From the description and illustration of the plunger mechanism 149 for each inspection cell, it will be seen that during movement of the multi-cell inspection unit 17, each plunger member will be shifted axially outwardly by the cooperative action of the cam 154 and the sleeve member 151. Although not specifically illustrated in the drawings, the cam 154 is constructed to present an outwardly extending camming surface adjacent the reject station 148 so that the spring 152 for each cell will be increasingly loaded at this point. It is also pointed out that when a can is properly seated within each inspection cell 18, the plunger member including the cap 153 thereof will be under a predetermined tension, the tension being produced by the spring 152.

Since the receptacles or cans to be inspected are normally urged outwardly of each inspection cell by the plunger mechanism associated therewith during the inspection cycle, means are provided for retaining the receptacle within each cell prior to locking of the receptacle therein as the multi-cell inspection unit 17 is rotated. To this end, the apparatus is provided with an irregularly shaped upper retaining plate 155 and a lower retaining plate 155a mounted on certain of the vertical support posts 13 and specifically those vertical support posts located between the feed-in station 146 and the acceptance discharge station 147. The upper retaining plate 155 and the lower retaining plate 155a are of substantially identical shape and are disposed in substantially parallel relation with respect to each other. The spacing between the upper retaining plate 155 and the lower retaining plate 155a is less than the height of the cell space or chamber 32 so that the inner marginal portions of the upper and lower retaining plates project inwardly of the individual inspection cells 18 during travel thereof between the feed-in station and the acceptance discharge station.

Referring now to FIG. 3, it will be seen that the respective inner edges of the upper and lower retaining plates 155 and 155:: respectively are positioned inwardly of a cell space or chamber 32 for each individual cell during predetermined travel thereof so that the inner edge 156 of the upper retaining plate and the inner edge 156a of the lower retaining plate actually engage and retain a can to be inspected in seated relation within the can guide members of each inspection cell. It will be noted, however, that these retaining plates and 155a terminate adjacent the acceptance discharge station whereby the can inspected will be released thereat unless the inspection mechanism locking means retains the can within the inspection cell.

It will also be seen that the retaining plates 155 and 155a carry a pair of cam rollers 157, one roller being positioned above the upper retaining plate 155 and one roller being positioned below the lower retaining plate 155a. The rollers are revolvably mounted on an axle 158, this axle being spring urged inwardly by a bifurcated plunger 159. It will be seen that the plunger 159 has a coil spring 160 embracing the same, the coil spring bearing against the bifurcation of the plunger and against the rear wall of a channel bracket 161. It will also be seen that the bracket 161 is mounted upon the upper and lower retaining plates 155 and 155a respectively.

It will also be seen that the peripheral surface of the rollers 157 are positioned rearwardly of the respective inner edges of the upper and lower retaining plates 155 and 155a. These rollers are positioned in obstructing relation to the path of travel of the cam elements 62 of each inspection cell 18 so that the cam elements of the inspection cells will be successively engaged by the rollers during rotative movement of the multi-cell inspection unit 17. Thus when the cam elements 62 for each inspection cell are engaged by the rollers 157, the cam elements will be shifted inwardly of the cell to initiate the inspection cycle.

It will also be seen that a second set of retaining plates are provided which are positioned between the acceptance discharge station 147 and the reject discharge station 148. The second set of retaining plates includes an upper retaining plate 162 and a lower retaining plate 162a suitably mounted on certain of the vertical support posts 13 which are disposed between these stations. It is pointed out that the upper and lower retaining plates 162 and 162a are of substantially identical shape and are disposed in substantially parallel relation with the inner edges thereof extending into the inspection cells during movement of the cells between the acceptance discharge station and the reject discharge station. Thus the inner edge 163 of the upper retaining plate 162 and the inner edge 163a of the lower retaining plate 162a actually constitute means for positively retaining the cans within the cells through movement of the inspection cells between the acceptance discharge station and the reject discharge station.

OPERATION During operation of the inspection apparatus 10, the receptacles or containers to be inspected will be fed by conventional gravity feed conveyor means or other conveyor means into the in-feed mechanism 112. It is pointed out that while the apparatus 10 is specifically designed to inspect generally rectangular shaped containers such vas sealed metal cans, it is contemplated that the apparatus and method described herein can be utilized to inspect sealed receptacles or containers having other shapes and configurations.

As the containers or cans designated by the reference character C are successively fed into the in-feed mechanism 112, those cans which are so deformed that the cans will not pass beneath the first skimmer belt 118 will be immediately impelled laterally by the skimmer belt. However, those cans which are vertically compressed and are laterally distended will pass beneath the first skimmer belt but will be tilted by co-action of the fixed vertical plate 126, the spring urged pressure plate 127 and the track member 130, so that this type of deformed can will be engaged and quickly impelled laterally by the second skimmer belt 132. Those cans or containers which pass below and beyond the second skimmer belt 132 will be impelled by the accelerator elements 137 into the inspection cell 18 which has been moved into registering relation with the pathway defined by the in-feed mechanism.

The can or container will then be seated in snug fitting relation with respect to the upper and lower can guide members 37 of the inspection cell and against the bias of the plunger mechanism 149 which will be retracted slightly. Th multi-cell inspection unit 17 will be continuously driven during operation of the apparatus by the drive mechanism therefor and the inspection cell will be shifted from the feed-in station 146 towards the acceptance discharge station 147. The outwardly disposed surface of the can positioned within the inspection cell will be quickly engaged by the respective inner edges of the upper and lower retaining plates 155 and 155a respectively so that the can to be inspected will be positively retained within the inspection cell against the bias of the associated plunger mechanism 149.

As the multi-cellular inspection unit 17 revolves from the feed-in station towards the acceptance discharge station, the rollers 157 engage the cam elements 62 of the upper and lower bead inspection mechanism 36 for each cell and produce retractive movement of the respective upper and lower mask plate members relative to the associated tumbler carriage member and guide plate. When the mask plate member 49 of each bead inspection mechanism is shifted rearwardly, the apertures 54 will be moved into registering relation with the pins 44 in the associated tumbler carriage member. In the event that the container or can to be inspected has no deformities in the upper anad lower beads, upward movement of the tumbler pins 44 will be prevented by the respective upper and lower beads of the container as the same is seated in the inspection cell. Therefore when the cam elements 62 for each cell are moved past the rollers 157, the spring 56 for each mask plate member 49 will urge the same forwardly to its returned position.

During this bead inspection operation, the lock member 76 will be carried rearwardly by its associated mask plate member and will be cammed by the camming surface 47a on the associated guide plate 47 so that the lock member 76 of both the upper and lower bead inspection mechanism will be disposed in obstructing relation with the rear portion of the bead of the receptacle. Upon retraction of the upper and lower mask plate members 49, the associated lock members will be returned to their retracted position by the associated spring elements which normally urges the lock member into its co-planar relation with its mask plate member.

The drive shaft 94 will also be axially retracted during the bead inspection operation and the rectilinear movement thereof will be transmitted through the racks 93 and through the gear trains to the cam shafts 86 and thereby cause the rotary cam elements to be revolved. Rotation of the rotary cam elements 87 causes swinging movement of the feeler elements 83 whereby the arcuate inner feeler surfaces 83a of the feeler elements will be moved through the concavity of the container which occurs when the contents of the container have been packed under a predetremined vacuum. These feeler elements 83 are spaced a predetermined distance so that they will be moved through the zone wherein the greatest degree of concavity occurs if a sufficient minimum predetermined vacuum or negative pressure is present within the can to be inspected. Thus the feeler elements and cam actuators therefor serve to measure the exterior width of the cans at the zone of the opposed walls where the expected greatest concavity will occur in the event that the minimum vacuum exists within the can. If the minimum predetermined vacuum does exist, the cam elements 87 will be allowed to revolve through 360 and the feeler elements will clear the walls of the can in their oscillating movement.

In the event that an insufficient vacuum or negative pressure is present within the can or container to be inspected, the sides of the container will not be collapsed inwardly to the degree to permit clearing of the cam actuated feeler elements 83 during oscillating movement thereof. Thus the cam elements 87 will not be able to revolve through an orbit of 360 and each cam element acting through the associated gear train and rack 93 of the drive transmitting sleeve 92, will lock the drive transmitting sleeve 92 and permit relative movement thereof with respect to the drive shaft 94. Therefore upon further retractive movement of the drive shaft 94, the lock member 96 associated therewith will become disengaged from the lock engaging member 100 on the drive transmitting sleeve 92 and will be urged upwardly into engaging relation with the hook element of the lock supporting member 73.

When the lock member 96 engages the hook element 75, the lock supporting member along with the lower mask plate member will also be urged rearwardly to cause the lock member 76 to be cammed upwardly into obstructing relation with respect to the head of the can being inspected. Therefore even though the upper and lower beads of the can are not damaged, the can will be retained within the inspection cell when an insufficient vacuum exists. The reciprocating movement of the drive shaft 94 is such that the lock member 76 will be locked against the lower surface of the can, in the event that an insufiicient vacuum exists therein, during movement of the associated inspection cell as it moves past the acceptance discharge station. It is pointed out that as the inspection cell moves past the acceptance discharge station, the upper and lower retaining plates and 155a will no longer be disposed in retaining relation with the can being inspected, and the inspection cell will not have been moved sufficient distance so that the retaining plates 162 and 162a retain the can within the cell. Therefore the feeler elements and the lock member 76 serve to retain the can in the inspection cell in the event that such a can has an insuffieient negative pressure or partial vacuum therewithin.

During further rotative movement of the multi-cell inspection unit 17, the drive shaft 94 will be axially extended to its original position thereby allowingthe lock member 96 to be interlocked with the lock engaging member 100 and also permitting return of the mask member and lock member 76 associated therewith to their original extended position. The inspection cell in which the defective can is positioned will have been moved in its orbit of rotation to a position wherein the upper and lower retaining plates 162 and 162a engage and retain the can within the inspection cell and the lock member 96 when interlocked with the lock engaging member 100 will cooperate therewith to urge the lock mounting member 95 in a retractive direction. This action will revolve the cam elements 87 whereby the feeler elements will be relived from gripped relation with respect to the can being inspected. It will therefore be seen that the upper and lower plates 162 and 162a after passage of the inspection cell beyond the acceptance discharge station comprise the sole retaining means of the can within the inspection cell 18.

In the event that the container or can being inspected has a defective bead at its upper or lower peripheries, one of the pins 44 or tumblers will escape upwardly into the mask plate member adjacent the area formed by the deformed bead. When this occurs, the mask plate member 49 will be prevented from returning to its extended position by the interengagement of the shoulder of the escaped pin 44 with the mask plate member so that the mask plate member is retained in its retracted position. As pointed out above, when the mask plate member is in its retracted position, the lock member 77 will extend upwardly into interlocked or obstructing relation with respect to the can or container being inspected. Thus the container will be locked within the inspection cell by the lock member 76 and the interlocked relation between. h pin or pins 44 with respect to the mask plate member, and the mask plate member 49 will be retracted until the support rods 66 are moved axially outwardly to permit seating of the tumbler carriage member 41 upon the convex support elements 67. The cam plates 197 for the support rods 66 are arranged and constructed so that the support rods will not be axially extended until the associated inspection cell 18 is moved beyond the acceptance discharge station. It will be therefore be seen that as the support rods 66 are extended, the convex support elements will be moved into registering relation with the arcuate recesses 68 in the associated tumbler carriage member 41. The arcuate recesses in the tumbler carriage member 41 will seat upon the convex support elements 67 so that the tumbler carriage member will have moved in a direction away from the associated mask plate member 49. Thus the pins 44 carried by the tumbler carriage member will be moved inwardly and any escaped pin will be moved out of obstructing relation with respect to the the associated mask plate member 49. The mask plate member 49 will then be caused to return to its normal extended position by action of the helical spring 46 and the lock member 76 will be allowed to return to its normal retracted position.

The defective can will then be retained in place in the inspection cell by the respective upper and lower retaining plates 162 and 162a respectively since the inspection cell will have moved at this time beyond the acceptance discharge station. The reaining plates 162 and 162a will retain the can or container within the inspection cell until the cell is revolved to the reject discharge station 148.

As the inspection cell reaches the reject discharge station, any defective can positioned therein will no longer be retained by the upper and lower retaining plates 162 and 162a since the inspection cell will be moved beyond these retaining plates. The sleeve member 151 of the plunger mechanism 149 will co-act with the cam 154 as the inspection cell reaches the reject discharge station to tension the spring 152 whereby the defective cans will be forcibly ejected from the inspection cell. This tensioning of the spring 152 by co-action of the sleeve memher 151, the cam 154 is desirable so that any deformed can which might be wedged in seated relation in the can guide members 137 will be ejected therefrom. Continued movement of the multi-cell inspection unit will return the inspection cell to the feed-in station 146 wherein the cycle will begin once again. As pointed out above, the multi-cell inspection unit revolves at approximately thirteen rpm. and the containers are continuously inspected and automatically discharged at the acceptance discharge station or automatically discharged at the reject discharge station.

It has been found through experience that containers such as the rectangular shaped metallic cans which contain a food product packed therein under a predetermined vacuum will have their opposed larger sides inwardly collapsed as a result of the presence of such a partial vacuum or negative pressure. It has been found through experience that the external dimension between the walls at the zone wherein the expected greatest degree of concavity will occur should be of a predetermined size. Therefore the sides must have collapsed inwardly a predetermined amount if the desired partial vacuum exists. If the minimum predetermined Vacuum is not present then the container or can was inelfectively packed or the can contains a leak. Similarly, damaged beads quite often results in minute leaks thereat and the foregoing apparatus and method permits complete and accurate inspection of such cans to determine damage to the can and to also determine if the minimum desirable predetermined vacuum is present.

From the foregoing, it will be seen that I have provided a novel method and apparatus for simultaneously inspecting containers packed with a product under a partial vacuum, to determine if a desirable predetermined negative pressure exists within the container, and to also determine the presence, if any, of any deformations or damage to the respective beads of the container.

It will also be seen from the preceding paragraphs that the novel method and apparatus is capable of high capacity continuous line operation and is therefore especially adaptable for use in meat packing plants and the like.

Thus it will be seen that I have provided a highly novel method and apparatus for inspecting packed containers, which permits a great saving in both time and labor with respect to conventional container inspection procedures. It Will, of course, be understood that various changes may be made in the form, details, arrangement and proportions of the various parts without departing from the scope of my invention.

What is claimed is: 1. A method of inspecting sealed symmetrically shaped containers, containing a product packed therein under a partial vacuum, and having upper and lower peripheral beads, to determine if a predetermined partial vacuum exists within the container, and to detect damage or deformation to the beads of the container, said method consisting in positioning a packed container to be inspected in predetermined orientation within an inspection cell, a pair of opposed walls of the container normally presenting concave external surfaces when the desired minimum predetermined vacuum exists therein so that the exterior dimension of the container between the opposed walls at the zone of greatest concavity is of predetermined size,

shifting the inspection cell to an acceptance discharge station wherein non-defective containers are discharged, then to a reject discharge station wherein defective containers are discharged, and thereafter return to the container receiver station,

during shifting of the inspection cell from the receiver station to the acceptance discharge station, mechanically measuring the exterior dimension of the container between the opposed walls thereof at the zone wherein the degree of greatest concavity occurs when the desired minimum predetermined vacuum exists therein,

simultaneously during said measuring operation inspecting the respective upper and lower beads of the container with mechanical sensing media to detect any deformation thereto,

automatically locking the container within the inspection cell in response to detection of deformation in one of the upper and lower beads of the container, and in response to determination that the measured zone of the container is greater than said predetermined size,

and retaining the defective container in interlocked relation within the inspection cell during travel thereof through the acceptance discharge station and ejecting the defective container at the reject station, but ejecting non-defective containers at the acceptance discharge station.

2. A method of inspecting generally rectangular shaped sealed containers, containing a product packed therein under a partial vacuum, and having upper and lower peripheral beads, to determine if a predetermined partial vacuum exists within the container, and to detect damage or deformation to the beads of the container, said method consisting in positioning a packed container to be inspected in predetermined orientation within an inspection cell, a pair of opposed walls of the container normally presenting concave external surfaces when the desired minimum predetermined vacuum exists therein so that the exterior dimensions of the receptacle between the opposed walls at the zone wherein the greatest degree of concavity occurs when the pre- 19 determined minimum vacuum exists is of predetermined size,

shifting the inspection cell to an acceptance discharge station wherein non-defective containers are discharged, then to a reject discharge station wherein defective containers are discharged, and thereafter return of the inspection cell to the container rece ver station,

during shifting of the inspection cell from the receiver station to the acceptance discharge station, mechanically measuring the exterior dimension of the container between the opposed walls thereof at the zone wherein the degree of greatest concavity occurs when the desired minimum predetermined vacuum exists therein,

simultaneously during said measuring operation inspecting the respective upper and lower beads of the container with mechanical sensing media to detect any deformation thereto,

automatically ejecting non-defective containers at the acceptance discharge station, automatically locking a defective container within the inspection cell in response to detection of deformation in one of the upper and lower beads of the container, and in response to a determination at the measured zone of the container is greater than said predetermined size,

and retaining the defective container in interlocked relation within the inspection cell during travel thereof through the acceptance discharge station and ejecting the defective container at the reject discharge station.

3. A method of inspecting generally rectangular shaped sealed containers, containing a product packed therein under a partial vacuum, to determine if a predetermined partial vacuum exists within the container, said method consisting in positioning a packed container to be inspected in predetermined orientation within an inspection cell, a pair of opposed walls of the container normally presenting concave external surfaces when the desired minimum predetermined vacuum exists therein so that the exterior dimension of the container between the opposed Walls at the zone of greatest concavity is of predetermined size,

shifting the inspection cell to an acceptance discharge station wherein non-defective containers are discharged, then to a reject discharge station wherein defective containers are discharged, and thereafter return of the inspection cell to the container receiver station,

during shifting of the inspection cell from the receiver station to the acceptance discharge station, mechanically measuring the exterior dimension of the container between the opposed walls thereof at the zone wherein the degree of greatest concavity occurs when the desired minimum predetermined vacuum exists therein,

automatically locking the container within the inspection cell in response to determination that the measured zone of the container is greater than said predetermined size,

and retaining the inspected container in interlocked relation within the inspection cell during travel thereof through the acceptance discharge station and ejecting the defective container at the reject discharge station, but permitting ejection of the non-defective conainer at the acceptance discharge station.

4. A method of inspecting sealed symmetrically shaped packed containers having upper and lower continuous peripheral beads, to detect damage or deformation to the beads ofthe container, said method consisting in positioning a packed container to be inspected in predetermined orientation within the inspection cell, shifting the inspection cell to an acceptance discharge 20 station wherein non-defective containers are discharged, then to a reject discharge station wherein defective containers are discharged and thereafter return to the container receiving station,

during shifting of the inspection cell from the receiver station to the acceptance discharge station, simultaneously inspecting the respective upper and lower beads of the container with mechanical sensing media to detect any deformation thereto,

automatically ejecting non-defective containers at the acceptance discharge station,

automatically locking the container within the inspection cell in response to detection of deformation in one of the upper and lower beads of the container, and retaining the defective container in interlocked relation within the inspection cell during travel thereof to the acceptance discharge station and ejecting the defective container at the reject discharge station.

5. A method of inspecting in one cycle of operation, a sealed symmetrically shaped container, containing a product packed therein under partial vacuum, and having upper and lower peripheral beads, to determine if a predetermined partial vacuum exists within the container, and to detect damage or deformation to the beads of the container, said method consisting in positioning a packed container to be inspected in predetermined orientation within the inspection cell, a pair of opposed walls of the container normally presenting concave external surfaces when the desired minimum predetermined vacuum exists therein so that the exterior dimension of the container between the opposed walls at the zone of the greatest concavity is of predetermined size,

revolving the cell in one cycle of operation from a container receiving station, wherein the container is received within the cell, to an acceptance discharge station wherein non-defective containers are discharged, then to reject discharge station wherein defective containers are discharged and thereafter return to the container receiver station,

mechanically measuring, during revolving movement of the inspection cell from the receiving station to the acceptance discharge station, the exterior dimension of the container between the opposed walls thereof at the zone wherein the greatest concavity occurs when the desired minimum predetermined vacuum exists therein,

simultaneously during said measuring operation, inspecting the respective upper and lower beads of the container with mechanical sensing media to detect any deformation thereto,

ejecting non-defective containers at the acceptance discharge station,

automatically locking the containers within the inspection cell in response to detection of deformation in one of the upper and lower beads of the container, and in response to a determination that the measured zone of the container is greater than said predetermined size,

and retaining the defective container in interlocked relation within the inspection cell during revolving movement thereof through and beyond the acceptance discharge station and ejecting the defective container at the reject station.

6. The method as defined in claim 5 wherein the containers being inspected are of substantially rectangular configuration.

7. Inspection apparatus for inspecting sealed symmetrically shaped containers, containing a product packed therein under partial vacuum, and having upper and lower peripheral beads, to determine if a desired predetermined partial vacuum exists within the containers, and to detect damage or deformation to the beads of the container, said apparatus comprising 21 an inspection cell structure defining an inspection chamber therewithin for receiving a container to be inspected therein, one pair of opposed walls of a container normally presenting concave external surfaces when the desired minimum predetermined vacuum exists therein so that the exterior dimensions of the container between the opposed walls at the zone wherein the greatest degree of concavity occurs, when the predetermined minimum vacuum exists, is

of a predetermined size,

structure mounting said inspection cell structure for travel from a container receiver station wherein the container is received therein, to an acceptance discharge station wherein non-defective containers are ejected, then to a reject discharge station wherein defective containers are discharged, and thereafter return to said container receiver station,

means within said inspection cell operable during shifting movement of the latter from said container receiver station to said acceptance discharge station to mechanically measure the exterior dimension of the container between the opposed walls thereof at the zone wherein the degree of greatest concavity occurs when the desired minimum predetermined vacuum exists therein,

bead inspection means within said inspection cell structure operable during operation of said measuring means to simultaneously engage the respective upper and lower beads of the container to detect any deformation thereto,

locking means within said inspection cell structure being automatically operable in response to detection of deformation in one of the upper and lower beads of the container, and in response to determination that the measured zone of the container is greater than said predetermined size, to releasably lock the container within the inspection cell structure during travel thereof through the acceptance discharge station, said looking means being automatically releasable when said inspection cell structure is shifted to the reject discharge station,

and ejection means operable to eject non-defective containers at the acceptance discharge station and being operable to eject the defective containers at the reject discharge station.

8. Inspection apparatus for inspecting sealed syme-trical- 1y shaped containers, containing a product packed therein under partial vacuum, and having upper and lower peripheral beads, to determine if a desired predetermined partial vacuum exists Within the container, and to detect damage or deformation to the beads of the container, said apparatus comprising an inspection cell structure defining an inspection chamber therewithin for receiving a container to be inspected therein, one pair of opposed walls of the container normally presenting concave external surfaces when the desired minimum predetermined vacuum exists therein so that the exterior dimension of the container between the opposed walls at the zone wherein the greatest degree of concavity occurs when the predetermined minimum vacuum exists is of predetermined size,

means for shifting said cell structure from a container receiver station wherein a container is received therein, to an acceptance discharge station wherein each non-defective container is discharged, then to a reject discharge station wherein each defective container is discharged, and thereafter return to the container receiver station,

means within said inspection cell operable during shifting movement of the latter to mechanically measure the exterior dimension of the container between the opposed walls thereof at the zone wherein the degree of greatest concavity occurs when the desired minimum predetermined vacuum exists therein,

upper and lower bead inspection mechanisms within said inspection cell structure, simultaneously operable during operation of said measuring means to simultaneously engage the respective upper and lower beads of the container to detect any deformation thereto,

locking means within said inspection cell structure being automatically operable in response to detection of deformation in one of the upper and lower beads of the container and in response to determination that the measured zone of the container is greater than said predetermined size, to relcasably lock the container within the inspection cell structure. during travel thereof through and beyond the acceptance discharge station,

said locking means being automatically releasable when said inspection cell structure is shifted to the reject discharge station,

and ejection means operable to eject non-defective containers at said acceptance discharge station and to eject the defective containers at the reject discharge station. 9. The apparatus as defined in claim 8 wherein each of said bead inspection mechanisms includes a pair of carriage members mounted at the upper and lower portions of said inspection chamber,

each of said carriage members having a plurality of pin elements shif-tably mounted thereon and arranged in a pattern corresponding generally to the configuration of the adjacent bead of the container to be inspected, each of said pins being shiftable from a retracted position to a bead engaging position to engage the adjacent surface portion of the container head during said inspection operation and for return to said retracted position if the adjacent surface portion of the bead is not deformed, and each pin being shiftable beyond said bead engaging position to an escape position when the adjacent surface portion of the container head to be engaged is deformed,

and said lock means being operable to lock the defective container within the inspection cell when one of said pins is in the escape position during travel of the inspection cell structure through and beyond the acceptance discharge station and being releasable when said inspection cell structure is shifted to the reject discharge station.

It). The apparatus as defined in claim 8 wherein said measuring means comprises a pair of spaced-apart feeler elements mounted within said cell structure for oscillating movement towards and away from each other and through the concave spaces defined by the opposed concave walls of the container when the predetermined partial vacuum exists within the container, said feeler elements engaging the opposed walls of the container when the measured zone thereof is greater than the predetermined size,

and actuator means for oscillating said feeler elements during travel of said cell structure.

11. Inspection apparatus for inspecting generally rectangular shaped sealed containers, containing a product packed therein under a predetermined partial vacuum, to determine if the predetermined desired partial vacuum exists within the container, said apparatus comprising an inspection cell structure defining an inspection chamber therewithin for receiving the packed container in predetermined position therein, one pair of opposed walls of the container normally presenting concave external surfaces when the desired minimum predetermined vacuum exists therein so that the exterior dimensions of the container between the opposed walls at the zone wherein the greatest degree of concavity occurs, when the predetermined vacuum exists, is of predetermined size,

structure mounting said inspection cell for travel from a container receiver station wherein a container is 

1. A METHOD OF INSPECTING SEALED SYMMETRICALLY SHAPED CONTAINERS, CONTAINING A PRODUCT PACKED THEREIN UNDER A PARTIAL VACUUM, AND HAVING UPPER AND LOWER PERIPHERAL BEADS, TO DETERMINE IF A PREDETERMINED PARTIAL VACUUM EXISTS WITHIN THE CONTAINER, AND TO DETECT DAMAGE OR DEFORMATION TO THE BEADS OF THE CONTAINER, SAID METHOD CONSISTING IN POSITIONING A PACKED CONTAINER TO BE INSPECTED IN PREDETERMINED ORIENTATION WITHIN AN INSPECTION CELL, A PAIR OF OPPOSED WALLS OF THE CONTAINER NORMALLY PRESENTING CONCAVE EXTERNAL SURFACES WHEN THE DESIRED MINIMUM PREDETERMINED VACUUM EXISTS THEREIN SO THAT THE EXTERIOR DIMENSION OF THE CONTAINER BETWEEN THE OPPOSED WALLS AT THE ZONE OF GREATEST CONCAVITY IS OF PREDETERMINED SIZE, SHIFTING THE INSPECTION CELL TO AN ACCEPTANCE DISCHARGE STATION WHEREIN NON-DEFECTIVE CONTAINERS ARE DISCHARGED, THEN TO REJECT DISCHARGE STATION WHEREIN DEFECTIVE CONTAINERS ARE DISCHARGED, AND THEREAFTER RETURN TO THE CONTAINER RECEIVER STATION, DURING SHIFTING OF THE INSPECTION CELL FROM THE RECEIVER STATION TO THE ACCEPTANCE DISCHARGE STATION, MECHANICALLY MEASURING THE EXTERIOR DIMENSION OF THE CONTAINER BETWEEN THE OPPOSED WALLS THEREOF AT THE ZONE WHEREIN THE DEGREE OF GREATEST CONCAVITY OCCURS 